The present invention relates to the field of electrical connection and, more particularly, a method of forming an electrical connector onto a substrate.
Various techniques exist in the prior art for making electrical connections between electronic components. These techniques typically use solder ball or solder column connections, wire bond pads or pins, or flexible connector arrangements. Thermal cycling fatigue limitations further limit the size of substrate that can be used for solder ball or solder column connections. Solder ball and solder column connections also have limitations because of the amount of space they require.
Pin arrangements, likewise, have space limitations. For example, the connectors to which the pins are attached utilize metal compression bits as pin sockets. Such structure, in itself, requires a relatively large amount of space and additional space must also be allocated for the flexing movement upon pin insertion. Moreover, these pin sockets are typically soldered into the next level of assembly, using additional space for holes and/or surface lands.
Flexible connectors are a viable option but there are difficulties inherent in such connectors. First, such flexible connectors are susceptible to fatigue. Second, each flexible connector must be individually connected to the substrate, thereby making manufacturability and cost an issue.
In addition to the connectors described above, various other connector techniques have been developed for connecting electronic components.
Boyd et al. U.S. Pat. No. 5,139,427, the disclosure of which is incorporated by reference herein, discloses a connector array in which individual connector elements are formed from sheet stock and then individually loaded into and captured by an insulating spacer.
Grabbe U.S. Pat. No. 5,173,055, the disclosure of which is incorporated by reference herein, discloses an area array connector in which connector elements are formed in a metallic sheet, laminated to a nonmetallic sheet, punched to isolate the connector elements and then joined to a substrate. The nonmetallic sheet is then removed to leave the individual connector elements.
Walker et al. U.S. Pat. No. 5,299,939, the disclosure of which is incorporated by reference herein, discloses an array of spring connectors which are formed by deposition and photoetch processes.
Roberts U.S. Pat. No. 5,343,616, the disclosure of which is incorporated by reference herein, discloses the formation of a conductive network wherein a metal sheet is coined to form ridges and then is glued to an insulator. Portions of the metal sheet are then ground away to isolate portions of the metal sheet which form contacts.
In view of the above, it is purpose of the present invention to have an electrical connector that is formed in an array and easily attached to a substrate.
It is another purpose of the present invention to have an electrical connector attached to a substrate that is manufacturable and relatively modest in cost.
These and other purposes of the present invention will become more apparent after referring to the following description considered in conjunction with the accompanying drawings.
The purposes of the invention have been achieved by providing, according to a first aspect of the invention, a method of forming an electrical connector comprising:
providing a metallic sheet having a plurality of connector blanks formed therein, each of the connector blanks having a base portion, a contact portion and a singulation arm;
forming each of the connector blanks into a connector having a predetermined shape wherein each of the connectors remain connected to the metallic sheet by their respective singulation arms and wherein the singulation arms are nonplanar with respect to the metallic sheet;
joining the base of each of the connectors to a first substrate; and
severing the singulation arms to separate each of the connectors from the metallic sheet wherein the base of each of the connectors is joined to the first substrate and the contact portion is adapted for contacting a second substrate.
According to a second aspect of the invention, there is provided a method of forming an electrical connector comprising:
providing a first metallic sheet having a plurality of connector blanks formed therein, each of the connector blanks having a base portion, a contact portion and a singulation arm;
forming each of the connector blanks of the first metallic sheet into a connector having a predetermined shape wherein each of the connectors remain connected to the first metallic sheet by their respective singulation arms, the metallic sheet having a perforation at least as large as the base portion of the connectors adjacent to each of the connectors;
providing a second metallic sheet having a plurality of connector blanks formed therein, each of the connector blanks having a base portion, a contact portion and a singulation arm;
forming each of the connector blanks of the second metallic sheet into a connector having a predetermined shape wherein each of the connectors remain connected to the second metallic sheet by their respective singulation arms, the metallic sheet having a perforation at least as large as the base portion of the connectors adjacent to each of the connectors;
placing the first and second metallic sheets together so that each connector of one of the metallic sheets fits into the perforation adjacent to each of the connectors of the other of the metallic sheets;
joining the base of each of the connectors to a first substrate; and
severing the singulation arms to separate each of the connectors from the metallic sheet wherein the base of each of the connectors is joined to the first substrate and the contact portion is adapted for contacting a second substrate.
According to a third aspect of the invention, there is provided a method of forming an electrical connector comprising:
providing a metallic sheet having a plurality of connector blanks formed therein, each of the connector blanks having a base portion, a contact portion and a singulation arm;
forming each of the connector blanks into a connector having a predetermined shape wherein each of the connectors remain connected to the metallic sheet by their respective singulation arms and wherein the singulation arms are nonplanar with respect to the metallic sheet;
joining the base of each of the connectors to a first substrate;
severing the singulation arms to separate each of the connectors from the metallic sheet wherein the base of each of the connectors is joined to the first substrate; and
placing a second substrate adjacent to the first substrate so that each of the contact portions of the connectors contacts the second substrate.
According to a fourth aspect of the invention, there is provided a method of forming an electrical connector comprising:
providing a first metallic sheet having a plurality of connector blanks formed therein, each of the connector blanks having a base portion, a contact portion and a singulation arm;
forming each of the connector blanks of the first metallic sheet into a connector having a predetermined shape wherein each of the connectors remain connected to the first metallic sheet by their respective singulation arms, the metallic sheet having a perforation at least as large as the base portion of the connectors adjacent to each of the connectors;
providing a second metallic sheet having a plurality of connector blanks formed therein, each of the connector blanks having a base portion, a contact portion and a singulation arm;
forming each of the connector blanks of the second metallic sheet into a connector having a predetermined shape wherein each of the connectors remain connected to the second metallic sheet by their respective singulation arms, the metallic sheet having a perforation at least as large as the base portion of the connectors adjacent to each of the connectors;
placing the first and second metallic sheets together so that each connector of one of the metallic sheets fits into the perforation adjacent to each of the connectors of the other of the metallic sheets;
joining the base of each of the connectors to a first substrate;
severing the singulation arms to separate each of the connectors from the metallic sheet wherein the base of each of the connectors is joined to the first substrate; and
placing a second substrate adjacent to the first substrate so that each of the contact portions of the connectors contacts the second substrate.